arXiv.org > hep-ph > arXiv:1209.3299
A Higgslike Dilaton
Brando Bellazzini, Csaba CsĂˇki, Jay Hubisz, Javi Serra, John Terning
(Submitted on 14 Sep 2012 (v1), last revised 5 Feb 2013 (this
version, v2))
We examine the possibility that the recently
discovered 125 GeV higgs like resonance actually corresponds to a
dilaton: the Goldstone boson of scale invariance spontaneously
broken at a scale f. Comparing to LHC data we find that a dilaton
can reproduce the observed couplings of the new resonance as long as
f ~ v, the weak scale. This corresponds to the dynamical assumption
that only operators charged under the electroweak gauge group obtain
VEVs. The more difficult task is to keep the mass of the dilaton
light compared to the dynamical scale, Lambda ~ 4 pi f, of the
theory. In generic, non-supersymmetric theories one would expect the
dilaton mass to be similar to Lambda. The mass of the dilaton can
only be lowered at the price of some percent level (or worse) tuning
and/or additional dynamical assumptions: one needs to suppress the
contribution of the condensate to the vacuum energy (which would
lead to a large dilaton quartic coupling), and to allow only almost
marginal deformations of the CFT.